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Journal of geographical sciences 2002年第4期12卷 397-404页

作者： DENG Xiangzheng, LIU Jiyuan, ZHUANG Dafang, ZHAN Jinyan, ZHAO Tao(Inst. of geographic sciences and Natural {2. {3., cas, beijing 100101, China) Inst. of geographic sciences and Natural {2. {3. CAS Beijing China

This paper discusses land-use changes in the interlock area of farming and pasturing (IAFP) in northern China. It presents detailed analyses of land-use features in the IAFP, which are controlled by the macro geomorphic units and geophysical conditions-constraints or advantages. Additionally, it selects some indicators, according to the availability in acquiring and processing their quantitative data, to analyze the canonical correlations between the typical conversion of grassland and geophysical conditions. The preliminary study indicates that the physical conditions are of great advantages to the development of grassland. There exists significant correlation between land use change and some geophysical conditions.

关键词： land use driving force interlock area of farming and pasturing China

A study of scale effect on specific sediment yield in the Loess Plateau,China

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Science China Earth sciences 2007年第1期50卷 102-112页

作者： YAN YunXia & XU JiongXin institute of geographical {2. and Natural {3. research, Chinese Academy of {2. Key Laboratory of Water Cycle and Related Land Surface Processes, Chinese Academy of {2., beijing 100101, China institute of geographical {2. and Natural {3. research Chinese Academy of Sciences Key Laboratory of Water Cycle and Related Land Surface Processes Chinese Academy of Sciences Beijing China

Based on data from 148 hydrometric stations in the Yellow River Basin, an analysis of regional scale relationship, or the relationship between specific sediment yield and drainage basin area, has been undertaken in the study area of the Loess Plateau. For different regions, scale relationship in log-log ordinate can be fitted by two types of lines: straight and parabola, and for each line, a function was fitted using regression analysis. The different scale relationships have been explained in terms of the difference in surface material distribution and landforms. To offset the scale-induced influence, calcu-lation has been done based on the fitted functions, in order to adjust the data of specific sediment yield to a common standard area. Based on the scaled data, a map of specific sediment yield was con-structed using Kriging interpolation. For comparison, a map based on the un-scaled data of specific sediment yield was also constructed using the same method. The two maps show that the basic pattern of specific sediment yield was basically the same. The severely eroded areas (Ys >10000 t km-2.-1) were at the same locations from Hekouzhen to Longmen in the middle Yellow River Basin. However, after the adjustment to a common standard area, the very severely eroded area (Ys >2.000 t km-2.-1) became much enlarged because after the adjustment, all the values of Ys in the lower river basin in those regions became much larger than before.

关键词： Loess Plateau erosion scale effect specific sediment yield.

On MSDT inversion with multi-angle remote sensing data

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Science China Earth sciences 2007年第3期50卷 422-429页

作者： FENG XiaoMing1,2.& ZHAO YingShi1 1 College of resources and Environment, Graduate University of the Chinese Academy of sciences, {2. 100049, China 2.institute of Remote Sensing Applications, Chinese Academy of sciences, beijing 100101, China College of resources and Environment Graduate University of the Chinese Academy of Sciences Beijing China institute of Remote Sensing Applications Chinese Academy of Sciences Beijing China

With the wavelet transform, image of multi-angle remote sensing is decomposed into multi-resolution. With data of each resolution, we try target-based multi-stages inversion, taking the inversion result of coarse resolution as the prior information of the next inversion. The result gets finer and finer until the resolution of satellite observation. In this way, the target-based multi-stages inversion can be used in remote sensing inversion of large-scaled coverage. With MISR data, we inverse structure parameters of vegetation in semiarid grassland of the Inner Mongolia Autonomous Region. The result proves that this way is efficient.

关键词： target-based multi-stages inversion multi-angle remote sensing wavelet transform

Ecological response to the climate change on the northern slope of the Tianshan Mountains in Xinjiang

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Science China Earth sciences 2005年第6期48卷 765-777页

作者： CHEN Xi1, LUO Geping1, XIA Jun2. ZHOU Kefa1, LOU Shaoping3.& YE Minquan4 1. Xinjiang institute of Ecology and Geography, Chinese Academy of sciences, Urumqi 83.011, China 2. institute of geographical and resources sciences, Chinese Academy of sciences, beijing 100101, China 3. Urumqi Meteorological-satellite Land Station, Urumqi 83.011, China 4. Seismological Bureau of Xinjiang Uygur Autonomous Region, Urümqi 83.011, China Correspondence should be addressed to Chen Xi Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi China institute of geographical and {2. {3. Chinese Academy of Sciences Beijing China Urumqi Meteorological-satellite Land Station Urumqi China Seismological Bureau of Xinjiang Uygur Autonomous Region Urümqi China

The Tianshan Mountains is a high and huge mountain body lying across the central part of Xinjiang, China, and is also the main area where the runoff forms in Xinjiang. In this paper, a set of RS-based study methods is put forward for deriving the information about the natural change of the ecology in arid areas, and the relationship between the climate change trend and the corresponding ecological response on the northern slope of the Tianshan Mountains since recent 40 years is analyzed from the scales of the land cover ecosystems and landscapes based on the observed data of climate, hydrology, modern glaciers and lakes on the northern slopes of the Tianshan Mountains since recent 40 years and the satellite RS data since recent 10 years by using the RS and GIS technologies. The results are as follows: (1) The overall trend of climate change on the northern slope of the Tianshan Mountains since recent 40 years is that both air temperature and precipitation are increased, especially the increase amplitudes of air tempera-ture, precipitation and annual runoff volume are high since the decade of the 1990s; (2. the in-tegrated indexes of the vegetation in all the geographical divisions on the northern slope of the Tianshan Mountains are obviously increased since recent 10 years, especially in the artificial oases and the foothill belts, such a change trend is advantageous for improving the vegetation ecology; and (3. the vegetation ecology in the arid areas is extremely sensitive to the climate change, the vegetation coverage and the biomass on the northern slope of the Tianshan Moun-tains are continuously increased because of the climate change since recent 10 years, their in-crease amplitudes in the plains and during the late stage are obviously higher than that in the mountainous regions and during the early stage.

关键词： north slope of the Tianshan Mountains, climate change, hydrological change, natural change of ecology,RS and GIS, vegetation index.

research on the multi-level intake water temperature effect of the Yalong River Jinping-I hydropower project

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Science China(Technological sciences) 2011年第S1期54卷 125-132页

作者： WU ShiYong 1,CAO Wei 1,WANG HongMei 1,SUN ShuangKe 2.&CHEN QiuWen 3.1 Ertan Hydropower Development Company,Ltd.,Chengdu 610051,China 2.China institute of Water {3. and Hydropower {2.,beijing 10003.,China 3.{2. Center for Eco-Environmental sciences,Chinese Academy of sciences,beijing 100085,China Ertan Hydropower Development Company Ltd. Chengdu China China institute of Water resources and Hydropower {2. Beijing China research Center for Eco-Environmental sciences Chinese Academy of Sciences Beijing China

Based on the discussion of the multi-level intake application status of high dam reservoir,this paper takes the Jinping-I hydropower project reservoir in the Yalong River as an example,which is shaped by the highest 3.5 m high arch dam,and carries out the forecasting research on the reservoir temperature by numerical simulation and physical model *** paper studies the intake effect of withdrawing the surface warm water by the stoplog gates inlets and verifies the reliability of the mathematical model by comparative *** results show that for a high dam hydropower station,taking the appropriate multi-level intake measure can withdraw the surface warm water in the spawning season and provide a favorable environment for the fish *** technical ideas and implementation scheme are adopted in this *** can provide technical reference for the solutions of similar problems in the future and it also has important engineering significance on the research of water temperature in large deep reservoirs.

关键词： water temperature multi-level intake Jinping-I hydropower project

Variation properties of ionospheric eclipse factor and ionospheric influence factor

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Progress in Natural Science:Materials International 2005年第6期15卷 573-576页

作者： ZHAO Chunmei 1,2.*, YUAN Yunbin1, OU Jikun1 and CHEN Jinping3.1. institute of Geodesy and Geophysics, Chinese Academy of sciences, Wuhan 43.077, China 2. Graduate School of Chinese Academy of sciences, beijing 10003., China 3. Department of Precision Instrument and Mechanology, Tsinghua University, beijing 100084, China) institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Graduate School Chinese Academy of Sciences Beijing 100039 China Department of Precision Instrument and Mechanology Tsinghua University Beijing 100084 China

The concepts and calculation methods of ionospheric eclipse factor (IEF) and ionospheric influence factor (IFF) are further illustrated. The temporal and spacial variation properties of IEF and IFF are studied, which shows that the properties are influenced by the geographic position and season. The possibility of improving the precision of using GPS data to determine ionospheric delay based on the above variation properties is also analysed.

关键词： GPS Ionospheric eclipse factor Ionospheric influence factor

Carbon dioxide exchange and the mechanism of environmental control in a farmland ecosystem in North China Plain

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Science China Earth sciences 2006年第S2期49卷 226-240页

作者： LI Jun, YU Qiang, SUN Xiaomin, TONG Xiaojuan, REN Chuanyou, WANG Jing, LIU Enmin, ZHU Zhilin & YU Guirui institute of geographic {2. and Natural {3. research, Chinese Academy of {2., beijing 100101, China Graduate University of the Chinese Academy of {2., beijing 100049, China College of {3. and Environmental studies, beijing Forestry University, beijing 100083. China institute of geographic {2. and Natural {3. research Chinese Academy of Sciences Beijing China Graduate University of the Chinese Academy of sciences Beijing China College of resources and Environmental studies Beijing Forestry University Beijing China

CO2.flux was measured continuously in a wheat and maize rotation system of North China Plain using the eddy covariance technique to study the characteristic of CO2.exchange and its response to key environmental factors. The results show that nighttime net ecosystem exchange (NEE) varied exponentially with soil temperature. The temperature sensitivities of the ecosystem (Q10) were 2.94 and 2.49 in years 2.02.2.03.and 2.03.2.04, respectively. The response of gross primary productivity (GPP) to photosynthetically active radiation (PAR) in the crop field can be expressed by a rectangular hyperbolic function. Average Amax andαfor maize were more than those for wheat. The values ofαincreased positively with leaf area index (LAI) of wheat. Diurnal variations of NEE were significant from March to May and from July to September, but not remarkable in other months. NEE, GPP and ecosystem respiration (Rec) showed significantly seasonal variations in the crop field. The highest mean daily CO2.uptake rate was -10.2. and -12.50 gC·m-2.d-1 in 2.03.and 2.04, for the maize field, respectively, and -8.19 and -9.50 gC·m-2.d-1 in 2.03.and 2.04 for the wheat field, respectively. The maximal CO2.uptake appeared in April or May for wheat and mid-August for maize. During the main growing seasons of winter wheat and summer maize, NEE was controlled by GPP which was chiefly influenced by PAR and LAI. Rec reached its annual maximum in July when Rec and GPP contributed to NEE equally. NEE was dominated by Rec in other months and temperature became a key factor controlling NEE. Total NEE for the wheat field was -77.6 and -152.2.gC·m-2.a-1 in years 2.02.2.03.and 2.03.2.04, respectively, and -12..1 and -165.6 gC·m-2.a-1 in 2.03.and 2.04 for the maize field, respectively. The cropland of North China Plain was a carbon sink, with annual -197.6 and -3.7.9 gC·m-2.a-1 in years 2.02.2.03.and 2.03.2.04, respectively. After considering the carbon in grains, the cropland became a carbon source, which was

关键词： net ecosystem exchange gross primary productivity ecosystem respiration carbon budget eddy covariance winter wheat summer maize.

Development of distributed time-variant gain model for nonlinear hydrological systems

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Science China Earth sciences 2005年第6期48卷 713-723页

作者： XIA Jun1, 2. WANG Gangsheng1, TAN Ge1, YE Aizhong2.& G. H. Huang3.1. Key Laboratory of Water Cycle & Related Land Surface Processes, institute of {3. {2. and Natural resources research, Chinese Academy of {2., beijing 100101, China 2. State Key Laboratory of Water resources & Hydropower Engineering {2., Wuhan University, Wuhan 43.072. China 3. Faculty of Engineering, University of Regina, 3.3. Wascana Parkway, Regina, Sask., S4S 0A2. Canada Correspondence should be addressed to Xia Jun Key Laboratory of Water Cycle & Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China State Key Laboratory of Water resources & Hydropower Engineering sciences Wuhan University Wuhan China Faculty of Engineering University of Regina Sask Canada

In this paper, a rainfall-runoff modeling system is developed based on a nonlinear Volterra functional series and a hydrological conceptual modeling approach. Two models, i.e. the time-variant gain model (TVGM) and the distributed time-variant gain model (DTVGM) that are built on the platform of Digital Elevation Model (DEM), Remote Sensing (RS) and Unit Hydro-logical Process were proposed. The developed DTVGM model was applied to two cases in the Heihe River Basin that is located in the arid and semiarid region of northwestern China and the Chaobai River basin located in the semihumid region of northern China. The results indicate that, in addition to the classic dynamic differential approach to describe nonlinear processes in hy-drological systems, it is possible to study such complex processes through the proposed sys-tematic approach to identify prominent hydrological relations. The DTVGM, coupling the advan-tages of both nonlinear and distributed hydrological models, can simulate variant hydrological processes under different environment conditions. Satisfactory results were obtained in fore-casting the time-space variations of hydrological processes and the relationships between land use/cover change and surface runoff variation.

关键词： hydrological process, nonlinearity, time-variant gain model, distributed hydrological model.

Origin Distribution Patterns and Floating Population Modeling:Yiwu City as a Destination

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Chinese geographical Science 2012年第3期22卷 367-380页

作者： LI Hongsheng WANG Yingjie HAN Jiafu State Key Laboratoty of resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Existing quantitative migration studies are mainly at the inter-region or inter-province level for lacking of detailed geo-referenced migration ***,few of them integrate explorative spatial data analysis and spatial regression model into migration *** on aggregated registered floating population data from 2.05 to 2.08,the phenomena that population floating to Yiwu City in Zhejiang Province is analyzed at the provincial and county *** spatial layout of Yiwu's pull forces is proved as a V-shaped pattern excluding Sichuan Province based on map visualization *** the migration ratio in 2.07 as an explanatory variable,two models are compared using ordinary least square,spatial error model and spatial lag model methods for county-level data in Jiangxi and Anhui *** model with migration stock provides an improved fitting over the model without migration stock according to the model fitting *** floating population flocking into Yiwu City from Jiangxi is determined mostly by migration stock while the determinant factors are migration stock and distance to Yiwu City for *** distance-decay effect is true for migration flow from Anhui to Yiwu City while the distance rule is not confirmed in Jiangxi with the best fitting *** correlation between per capita net income of rural labor forces and migration ratio is not significant in Jiangxi and significant but at the 0.1 level only in *** analysis shows that the distance,income and man-land ratio are important factors to explain population floating at earlier ***,as the dynamic population floating process evolves,the determinant factor would be migration stock.

关键词： floating population origin distribution visualization spatial regression model Yiwu City GIS

Ecological hydraulic radius model to calculate instream flow requirements for transporting sediment in the western water transfer region

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Science China(Technological sciences) 2009年第11期52卷 3401-3405页

作者： MEN BaoHui1 & LIU ChangMing2.1 Renewable Energy institute, North China Electric Power University, beijing 102.06, China 2.Key Laboratory of Water Cycle and Related Land Surface Process, institute of geographical sciences and Natural resources research, Chinese Academy of sciences, beijing 100101, China Renewable Energy institute North China Electric Power University Beijing China Key Laboratory of Water Cycle and Related Land Surface Process Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China

Transporting sediment is a natural function of the river. To maintain the normal evolution of the river certain amount of water flow is required, which is called the instream flow requirements for transporting sediment (IFRTS). We defined the permitting flow velocity by the conception of IFRTS, and also put forward the ecological hydraulic radius model (EHRM) to estimate IFRTS. The calculating process of EHRM is explained by the example of Daofu Hydrological Station on Xianshui branch of Yalong River in the west line first-stage construction of South-North Water Transfer Project. The result shows that the IFRTS occupied 2..7%―59.5% of annual mean discharge in flood season, the average of IFRTS was about 100.2.m3.s during 1966―1987, it is close to the IFRTS 90 m3.s calculated by IFRTS conception. Hence, it is feasible to use EHRM to calculate IFRTS.

关键词： ecological hydraulic radius model (EHRM) instream flow requirements for transporting sediment (IFRTS) permitting flow velocity ecological hydraulic radius for transporting sediment